We begin with the dramatic start to the nascar season. The stadium packed with 167,000 fans for the celebrated daytona 500 today. They were there to watch jimmie johnson cross the finish line and take the season's first prize. But in the back of their minds, there were these images of the terrifying end to yesterday's preliminary race. A spin-out involving a dozen cars. One mangled car smashing into the fence and breaking into pieces. Some pieces flying into the stands, striking spectators and After a frantic night repairing all of that damage, today's race went on. The lingering questions about fan safety remain. Abc's matt gutman is at the speedway with the latest. Reporter: Tonight it was vintage nascar, the fireworks, bravado, and the speed. Jimmie johnson taking home the biggest trophy in nascar. Danica patrick, who made history earlier this week by taking pole position, finished eighth. The force with which these cars come around that bend is absolutely incredible. They're flying in here at 200 miles per hour, and when they pass, you can't even hear anything. And it was that speed which overshadowed today's race when -- an artillery blast of debris right into the stands on the last lap of the daytona nationwide yesterday. A pack of cars pirouetting at the finish line. And as kyle larson's number 32 car cart wheeled into the stands. All you can do is get down. You could see the stuff coming. Reporter: You can see larson's car disintegrate, one of his tires launched into the crowd. 28 injured, two of them seriously. Even a minor among those hospitalized. And look closely, this spectator ducking and hopping over wreckage. Now each one of these weighs about 75 pounds. Imagine one of these flying into those stands at 200 miles per hour. Larson's engine piercing the metal catch fencing between spectators and the track. The car was right here. The axle, the engine, everything. Right here, and it was hot. Reporter: Even drivers like dario franchitti wants more protection for fans. Tweeting his demand for, quote, an alternative to catch fencing. There has to be a better solution. Reporter: But look at that fence today. Mended with uncanny speed. And fans out by the tens of thousands. Many in the same seats. A piece of wire off the fence came up and hit me in the back. A guy right next to us got hit in the leg and cut up pretty bad. Reporter: How many people got hit yesterday or saw something yesterday? Brandon bauman said he was terrified to return. You know at any moment somebody can get turned again and something can break loose, and that's how the racing is. You just never know. We just spoke to officials here and they told us seven people remain hospitalized from that crash yesterday. Nascar says its top priority is protecting its fans. Paula?

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